Author Institution: Department of Physics, The Pennsylvania State UniversityWe have observed the emission spectrum of the two abundant isotopes of HCl in the spectral region from 2055 to 3178 cmβ1 using a spectrometer equipped with a 40 cm echelle. The maximum values of v and J were 5 and 30, respectively. The spectrum was produced by means of a low pressure flame in a multiple reflection cell. The data, together with data from the high temperature absorption spectrum and recent FTS data, were used to calculate Dunham coefficients and potential constants